Hi,
Would you be considering a kickstarter for funding?
And maybe, focus only on Samsung devices so that it's a lot less work? (like galaxy store)
Saying that because the only good art app for android is infinite painter IMO, so you would be welcomed like kings if one day you decided to go both ways.
I have an iPad and a Samsung tab with Spen and I prefer using the Samsung a lot more. You can work for hours without having to charge your pen with the Spen. And the Apple pencil is so heavy...
Plus, the new Samsung S8 ultra with its 14in screen would be a huge asset for artists.